NEW YORK (AP) — Flu season in the U.S. is off to its earliest start in nearly a decade – and it could be a bad one.

Health officials on Monday said suspected flu cases have jumped in five Southern states, and the primary strain circulating tends to make people sicker than other types. It is particularly hard on the elderly.

“It looks like it’s shaping up to be a bad flu season, but only time will tell,” said Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention.